title: Maize LAZY1 mediates shoot gravitropism and inflorescence development through regulating auxin transport, auxin signaling, and light response.
abstract: Auxin is a plant hormone that plays key roles in both shoot gravitropism and inflorescence development. However, these two processes appear to be parallel and to be regulated by distinct players. Here, we report that the maize (Zea mays) prostrate stem1 mutant, which is allelic to the classic mutant lazy plant1 (la1), displays prostrate growth with reduced shoot gravitropism and defective inflorescence development. Map-based cloning identified maize ZmLA1 as the functional ortholog of LAZY1 in rice (Oryza sativa) and Arabidopsis (Arabidopsis thaliana). It has a unique role in inflorescence development and displays enriched expression in reproductive organs such as tassels and ears. Transcription of ZmLA1 responds to auxin and is repressed by light. Furthermore, ZmLA1 physically interacts with a putative auxin transport regulator in the plasma membrane and a putative auxin signaling protein in the nucleus. RNA-SEQ data showed that dozens of auxin transport, auxin response, and light signaling genes were differentially expressed in la1 mutant stems. Therefore, ZmLA1 might mediate the cross talk between shoot gravitropism and inflorescence development by regulating auxin transport, auxin signaling, and probably light response in maize.
authors.affiliation: National Maize Improvement Center of China, Beijing Key Laboratory of Crop Genetic Improvement, Coordinated Research Center for Crop Biology, China Agricultural University, Beijing 100193, People's Republic of China.
authors.forename: Zhaobin
authors.initials: Z
authors.lastname: Dong
authors.forename: Chuan
authors.initials: C
authors.lastname: Jiang
authors.forename: Xiaoyang
authors.initials: X
authors.lastname: Chen
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.forename: Lian
authors.initials: L
authors.lastname: Ding
authors.forename: Weibin
authors.initials: W
authors.lastname: Song
authors.forename: Hongbing
authors.initials: H
authors.lastname: Luo
authors.forename: Jinsheng
authors.initials: J
authors.lastname: Lai
authors.forename: Huabang
authors.initials: H
authors.lastname: Chen
authors.forename: Renyi
authors.initials: R
authors.lastname: Liu
authors.forename: Xiaolan
authors.initials: X
authors.lastname: Zhang
authors.forename: Weiwei
authors.initials: W
authors.lastname: Jin
mesh_terms: D000595:Amino Acid Sequence; D001692:Biological Transport / Q000235:genetics / Q000528:radiation effects; D002462:Cell Membrane / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D018522:Gravitropism / Q000235:genetics* / Q000502:physiology; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D007210:Indoleacetic Acids / Q000378:metabolism*; D056626:Inflorescence / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D008027:Light; D008855:Microscopy, Electron, Scanning; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D010940:Plant Proteins / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D018520:Plant Shoots / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000235:genetics / Q000528:radiation effects; D059467:Transcriptome; D003313:Zea mays / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism
chemical_list: D007210:Indoleacetic Acids; D010940:Plant Proteins; D049452:Green Fluorescent Proteins